PEACH SCAB AND ITS CONTROL. 55 
treatment. Selby (1904), Scott (1909), Scott and Ayres (1910), 
Scott and Quaintance (1911), and others showed conclusively that 
scab may be controlled to a degree which is entirely satisfactory 
commercially when the first fungicidal treatment is made about one 
month after the petals fall. The results of the writer, previously 
reported, offer further confirmation of this work. When the applica- 
tion is delayed so long as this, slight scab infection is to be expected, 
but it is usually confined to scattered, inconspicuous lesions about 
the peduncles. It appears conclusive, therefore, that the application 
of a fungicide at the time of the shedding of the calyces is not neces- 
sary to commercially satisfactory scab control, except possibly under 
very extreme conditions, though at times it may be of some value, 
and is relatively inexpensive when an application of arsenate of lead 
is made for the plum curculio at this time. 
Treatment about one month after petals fall. — The results of Selby 
(1898 and 1904), Scott (1908 and 1909), Scott and Ayres (1910), 
Clinton and Britton (1911), Scott and Quaintance (1911), Blake and 
Farley (1911), and others indicate the importance of the application 
of a suitable fungicide about one month after the petals fall. The 
results of the writer (plats 9, 10, 13, 14, 15, 17, 19, 20, 21, and 22) 
further confirm this work, showing clearly that for midseason varie- 
ties this is the primarily important treatment for scab. 
Treatment three to four weeks before the fruit is harvested. — The work 
cited in the preceding paragraph indicates the desirability of a further 
fungicidal treatment. If scab only were considered this would be 
made about two or three weeks after the preceding application, since 
previously reported life-history studies have shown that infections 
which occur later than six weeks before the fruit is harvested are not 
likely to become injurious. However, the fact that this treatment 
must, for the sake of economy, serve also as the final spray for brown- 
rot makes it necessary to delay it until three weeks or a month before 
the fruit is picked. 
VARIATION OF SCHEDULE FOR EARLY VARIETIES. 
The results of Scott and Ayres (1910), Scott and Quaintance (1911), 
the writer (plats 1, 2, 5, and 6), and others show that on early varie- 
ties commercially satisfactory scab control may be effected by a single 
thorough fungicidal treatment about one month after the petals fall 
and that under certain circumstances the later treatment may be 
omitted without serious loss of efficiency. In such cases the first 
and second treatments, as recommended for midseason varieties, will 
suffice. In cases where there is danger of serious outbreaks of brown- 
rot, however, the omission of the third application seems unwise. In 
such cases the three applications, as recommended for midseason 
varieties, should be made. 
